Iran says it is committed to reaching a nuclear deal with the U.S. and five world powers, who resume talks with Iranian officials this week.
The U.S. State Department says bilateral talks between U.S. and Iranian diplomats will take place Thursday in New York, ahead of the formal talks that begin Friday.
Analysts say the chances for a breakthrough are slim ahead of the November 24 deadline that was set after the two sides failed to reach a July target date for a deal.
Iranian Foreign Minister Javad Zarif said Iran is eager to resolve the issue. But he said during a speech at the Council on Foreign Relations the issue is being complicated by the U.S., which he said is "obsessed with sanctions."
"This deal would require the United States to lift the sanctions and now the reason Congress is objecting to this is that it wants to keep these sanctions. Yes, sanctions have become an end in themselves," Zarif said.
The two sides reached an interim deal last year to reduce U.S. sanctions in exchange for Iran freezing its uranium enrichment program.
Iran is pushing to preserve its ability to enrich uranium, which it says is to help generate electricity. The U.S. and many of its allies fear Iran is trying to achieve the capability of producing a nuclear bomb.